Flat panel speaker



FIG. 1 is a top, rear, left perspective view of a flat panel speaker, showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof, shown in an enlarged scale; and,

FIG. 7 is a bottom plan view thereof, shown in an enlarged scale.

Dotted lines shown in the drawings represent environmental subject matter and form no part of the claimed design. 

CLAIM The ornamental design for a flat panel speaker, as shown and described. 